This invention relates to a ball throwing machine used, e.g., for practicing batting balls and catching fly balls.
A prior art ball throwing machine is disclosed in U.S. Pat. No. 3,724,437. In the disclosed arrangement, a pair of counter-rotating wheels are used. A ball is nipped between the outer peripheral surfaces of said two rotary wheels, thereby accelerated and thrown forward.
In the aforesaid prior art machine, if the relative speed between the rotary wheels and the ball fed into between the rotary wheels is increased too high to throw the ball at high speed, a slip would be produced between the rotary wheels and the ball when the ball is nipped between the outer peripheral surfaces of the rotary wheels. In this case, the acceleration of the ball is insufficient and the ball cannot be thrown at high speed.
Further, said slip increases the rate of wear of the ball.